Polishing machine



March 15, 1932. A. LITTLEFIELD POLISHING MACHINE Filed June 24, 1927 5 Sheets-Sheet l WEE PM/L4 ATTORNEYS.

March 15, 1 932.

A. LITTLEFIELD POLI SHING MACHINE Filed June 24, 1927 3 Sheets-Sheet 2 INVENTOR. b

ATTORNEYS.

March 15, 1932. A, LITTLEFIELD POLISHING MACHINE 3 Sheets-Sheet 5 Filed June 24, 1927 I I I I I 1 IF ATTORNEYS.

Patented Mar. 15, 1932 trio" ARLON LITTLEFIELD, OF PROVIDENCE, RHODE ISLAND, ASSIGNOR TO NE'VT ENGLAND BUTT COMPANY, OF PROVIDENCE, RHODE ISLAND, A CORPORATION OF RHODE ISLAND POLISHING MACHINE Application filed June 24,

This invention relates to polishing machines more particularly adapted for use in smoothing and polishing the insulation. of electrical cables and the like; and the object of this invention is to provide an improved construction of such amachine having pair of clamp arms mounted to be rapidly rotated and to provide means for operating said arms to grip the work and to adjust the grip ping pressure of these arms while rapidly rotating.

A further object of the invention is the provision of means whereby the gripping ac tion of these arms will yield somewhat to permit the polishing blocks to ride over bunches in the surface of the wire covering.

The invention further consists in mounting all of the operating mechanism of each unit upon a single rotating tube, mounting this tube in bearings, mounting a drive pulley on the tub-e between the bearing and also mounting the clamping mechanism on that portion ofthe tube which extends forwardly beyond the bearings.

With these and other objects in view, the invention consists of certain novel features of construction, as will be more fully described, and particularly pointed out in the appended claims. A

In the accompanying drawings Figure 1 is a side elevation illustrating my improved machine having two separate sets of polishing devices arranged to be driven in opposite directions when "operating upon the work. 1

Figure 2 is a plan view with one of the guards broken away.

Figure 3 is a view partly in section showin the spring arms mounted on the overhanging end of the drive guide tube.

Figure 4 is a side elevation of one ofthe sets of polishing devices partly in section.

Figure 5 is' anend view on line 5-5 of Figure 2. I

Figure 6 is a sectional end view on line 66 of Figure 3.

Figure 7 is an edge view of the take-up guide sheave.

Figure 8 is a perspective view of one of the 1927. Serial No. 201,208.

Figure 11 is an end view of the polishing v locks as supported in clamping arms. It'is found in practice of advantage to provide in a pollshing machine of this character two separate and independent sets of polishing devices or units, each mounted on a separate tubularmember whlch 1s supported in a pair of bearings, the tubes being driven in opposite directions one by an open and the other by a cross belt and arranged to apply frictional pressure while rapidly revolving to the surface of the wire insulation as it travels lengthwise through the tubes. It is serves both as an element of safety to prevent injury to the attendant and also to prevent the throwing off of the polishing material while rapidly rotating". Also, I find it of ad vantage to pivotally mount each set of these clamping or polishing arms on the forward ly extending portion of its driving'tube and to provide means whereby these arms may be caused to press the friction blocks upon the work and to provide means whereby this pressure may be readily adjusted while the, heads are rapidly revolving. Also it is found of advantage to provide simple and effective means for mounting these arms to yield automatically and so adjust themselves to accommodate slightly varying sizes of insulation and to further yield when encountering a bunch or protuberance on the surface of the insulation sufficientlyto prevent rupturing the covering; and the following is a detailed description of the present embodiment of my invention and showing one means by which the polishing heads and also drive the take-up sheave 18 through the speed reducing driving gear mechanism 19.

On this bed portion of the machine are mounted two sets of polishing devices or units 20 and 2.1. The unit 20 is provided with a pulley 22 through which it is driven in one direction by the cross belt 15, while the unit 21 is provided with a pulley 23 which is driven in the opposite direction by the open belt 17. Both of these polishing devices or units are similarly constructed,.the forward unit comprising a tube 24 mounted on'ball bearings 25 and 26 in the bearing heads 27 and 28, respectively, and on this tube is mounted the drive pulley 23 between these bearingheads. he forward end of this tube overhangs the forward bearing 28 and on the outer end of the tube are fixed two pairs of oppositely-extending ears 29 in which are pivotally mounted at 30 a pair of friction arms31. These arms are designed to spring and so yield slightly when applying a polishing pressure to the surface of the work 32. Polishing blocks 33 are pivotally mounted at 34 in the working ends of these arms for frictionally engaging the surface of the work, which, in this case, is shown to be insulation on a wire or cable.

On the tube to the rear of the pivoting point of these arms is mounted a collar 35 to slide endways on the tube in the keyway 36 and this collar is connected through the connecting rods 51 to the ends 52 of the friction arms-31, and this-collar is grooved at .37 for the purpose presently described.

To the rear of this collar 35 is mounted another collar 54 which encircles a ball thrust bearing 55 and this second collar 54 is connected to the first collar by means of inturned attaching fingers 53 which extend into the groove 37 in the collar 35, above described. This thrust collar 54 is provided with holes 56 for the reception of the pivoting pins 38 in the operating yoke 39. This yoke is pivoted at 40 at one end to the forwardlyextending arm 41 connected to the bearing 28, while to the opposite side of this yoke is pivotally connected at 42 the forward end of the clamp arm operating rod 43'. The forward end of this rod is slidably mounted in the bracket 44' while its rear end is threaded as at 45 to extend through the threaded nut 46 which is rotatably mounted in the bracket 47 and to the outer end of this nut is attached an operating handle 48 and to the forward belt and as the clamp arms are operatively mounted on the forwardly-extending end of the tube they may be adjusted through the rod 43 by simply rotating the hand nut 46 to apply a polishing pressure upon the surface of the insulated wire, the arms, themselves, being of a size to yield slightly when gripping the surface of the insulation covering and also the connecting rods 51 are designed to stand at an angle as best illustrated in Figure 3, when the polishing blocks are in contact with the surface of the work, whereby when these blocks meet a protuberance on this surface instead of rupturing the same the arms are permitted to yield slightly and so force back the collar 35 through the yoke 39 causing the rod 43 and. its nut 46 to recede and compress the spring slightly and so prevent rupture or roughening up of this surface of this insulation.

Further, it is also found of advantage to' which latter guard is split transversely at its middle section and is hinged at 59 at one side and provided with a thumb piece (SO-on its opposite side whereby it may be readily opened for inspection of the polishing ends of the arms 31;

This guard also serves to prevent injury to the attendant and at the same time prevents the polishing material from being thrown about, which material may be applied by hand or in any suitable way, not shown, to the work. The work which is herein illus trated as insulated wire may be fed continuously through the machine to be operated upon and polished by the oppositely revolving polishing units; Thewire or cable is then wound around the driven take-up sheave 18 and is then ledto the usual reel (not shown).

It is found in practice that by positively connecting together the inner ends of the friction arms 31 by the'links 51 that the pressure these arms are caused to exert upon the work is quite equal and uniform and the pressure of one arm is not heavier than that of the other, which sometimes is not the case where the arms are not connected together.

My improved polishing machine is very simple and practical in construction, is effective in its operation and by its use wire or cable may be run at a rapid speed therethrough and the surface of the insulation be polished and at the same time reduced to a uniform diameter.

The foregoing description is directed solely towards the construction illustrated, but I reserve the privilege of resorting to all the mechanical changes to which the device is susceptible, the invention being defined and limited only by the terms of the appended claims.

I claim:

1. In a polishing machine, a tube, spaced bearings for supporting the tube, means for rotating the tube, a pair of friction applying arms pivotally mounted on the tube near its end, a collar mounted to slide axially 0n the tube, links connecting said collar with the inner ends of said arms, a collar operating yoke, and a spring pressed actuating rod acting thru said yoke to exert a yieldable pressure thru said arms upon the work.

2. In a polishing machine, a tube, a hearing for supporting each end of the tube, means for rotating the tube, a pair of friction-applying resilient arms pivotally mounted at one end of the tube, means acting thru a toggle joint connection on said arms for applying pressure to the work, and means for moving the toggle connections to change the relative positions of the said arms.

3. In a polishing machine, a tube, spaced bearings for supporting the tube, means for rotating the tube, a pair of friction applying resilient arms pivotally mounted on the tube near its end, a collar mounted to slide axially on the tube, links each pivotally connected at one end to said collar and pivotally connected at the other end to the ends of said arms, a collar operating yoke, and a spring pressed actuating rod acting through said yoke to exert a yielding pressure through said arms upon the work. 1

In testimony whereof I affix my si 7 ature.

ARLON LITTLEFIELD. 

